title: Diastereochemical differentiation of some cyclic and bicyclic beta-amino acids, via the kinetic method.
abstract: Stereochemical differentiation of five diastereomeric pairs of beta-amino acids, di-endo- and di-exo-2,3-disubstituted norbornane and norbornene amino acids, cis- and trans-2-aminocyclohexane-, 2-amino-4-cyclohexene-, and 2-aminocyclopentanecarboxylic acids, was investigated via the kinetic method with metal-bound trimeric complexes. This is the first time that diastereomers (di-endo/di-exo and cis/trans) have been differentiated with metal-bound trimeric complexes and the kinetic method. Moreover, determination of diastereochemical excess by the kinetic method was applied to norbornane beta-amino acids and cyclopentane beta-amino acids. Experiments showed that a remarkable differentiation of the studied diastereomers was achieved. It was observed that better selectivity values correlated to more rigid structures. The reference compounds for the studied beta-amino acids varied from alpha-amino acids to some beta-amino acids. In addition, variation of the metal ion (Cu(2+) and Ni(2+)) had some role in the selectivity values obtained. Ab initio and hybrid density functional theory calculations were performed to clarify the results obtained by mass spectrometry.
authors.affiliation: Department of Chemistry, University of Joensuu, Joensuu, Finland.
authors.forename: Anna R M
authors.initials: AR
authors.lastname: Hyyryläinen
authors.forename: Jaana M H
authors.initials: JM
authors.lastname: Pakarinen
authors.forename: Ferenc
authors.initials: F
authors.lastname: Fülöp
authors.forename: Pirjo
authors.initials: P
authors.lastname: Vainiotalo
mesh_terms: D000465:Algorithms; D000598:Amino Acids, Cyclic / Q000737:chemistry*; D003300:Copper / Q000737:chemistry; D003509:Cyclohexanecarboxylic Acids / Q000737:chemistry; D007700:Kinetics; D008958:Models, Molecular; D015394:Molecular Structure; D009532:Nickel / Q000737:chemistry; D009636:Norbornanes / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013237:Stereoisomerism; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000598:Amino Acids, Cyclic; D003509:Cyclohexanecarboxylic Acids; D009636:Norbornanes; D003300:Copper; D009532:Nickel